the yhmath fonts provide extensible parenthesis and other delimiters, as well as sqrts etc etc. Unfortunately it was found that the \biggl size is not correctly selected, as shown here
The charlist code in the metafont source looks correct, but we cannot find the reason for the discrepancy. I checked that it is not an error of the type1 fonts, it happens the same way with the mf fonts.
Detailed discussion with many more examples and test files are here: https://github.com/TeX-Live/yhmath/issues/3
The respective mf code follows:
charlist oct"000": oct"200": oct"020": oct"201":
oct"022": oct"202": oct"040": oct"203":
oct"204": oct"205": oct"206": oct"207": oct"210": oct"211":
oct"060"; % left parentheses
...
cmchar "\big left parenthesis";
beginchar(oct"000",7u#,rule_thickness#,2dh#-rule_thickness#);
adjust_fit(1.5u#,-.25u#); left_paren(hair,stem); endchar;
cmchar "\Big left parenthesis";
beginchar(oct"020",9u#,rule_thickness#,3dh#-rule_thickness#);
adjust_fit(2u#,-.25u#); left_paren(rule_thickness,.5[stem,bold]); endchar;
cmchar "\bigg left parenthesis";
beginchar(oct"022",11u#,rule_thickness#,4dh#-rule_thickness#);
adjust_fit(2.5u#,-.25u#); left_paren(rule_thickness+.2dw,bold); endchar;
cmchar "\Bigg left parenthesis";
beginchar(oct"040",11.5u#,rule_thickness#,5dh#-rule_thickness#);
adjust_fit(3u#,-.25u#); left_paren(rule_thickness+.4dw,bold+dw); endchar;
Any suggestion how to track this down and improve the display would be nice.
Thanks
Norbert
